The Bellevue City Council Tuesday again took up questions on where a future light rail line should be located in Bellevue, with an emphasis on the downtown area.

The public will have an opportunity to learn about four new downtown alternatives at an open house on Thursday. Sponsored by Sound Transit, the event will be 4 to 7 p.m., on the first-floor concourse of City Hall, 450 110th Ave. N.E.

The downtown options are part of Sound Transit's work on East Link, a light rail line approved by voters in 2008 as part of a regional ST2 package of transit projects. East Link includes the extension of light rail from Seattle, across Lake Washington on Interstate 90 to Bellevue, continuing to the Overlake Transit Center in Redmond.

New downtown route options include two street-level alternatives, one elevated alternative and one tunnel alternative. Two earlier options identified in May 2009 continue to be studied.

Last week, City Council members held an unusual joint meeting with the Sound Transit Board of directors to consider the new downtown options. Bellevue Council members are expected to make a recommendation in late March or early April on which alternative they prefer. The Sound Transit Board is slated to choose its downtown preference in late April.

The long-range timeline calls for Sound Transit to complete a final environmental review of all the East Link alternatives -- including those in the three Bellevue segments -- in late 2010, with a definitive decision by the board on routes and station locations by early 2011. East Link design work is slated from 2011 to 2013, construction is scheduled to begin by 2014, and light rail service to Bellevue is projected to start in 2020.